#9 Envelopes - 3 7/8 x 8 7/8

Key Summary:

• #9 envelopes measure 3 7/8 x 8 7/8 inches and are a staple in business correspondence.
• Popular for mailing invoices, statements, and return envelopes.
• Offered in regular, windowed, security, and remittance styles.
• Available in various paper finishes, weights, and colors.
• Customizable and compatible with printers, enhancing brand visibility and security.

At 3 7/8 x 8 7/8 inches, #9 envelopes offer just the right balance of compactness and functionality. They're a widely used commercial envelope size, often inserted into #10 envelopes as reply or return options. Their standardized dimensions make them compatible with most printers and form letters, ensuring ease of use across industries.

Compared to the slightly larger #10 (4 1/8 x 9 1/2), #9 envelopes are designed for inner-office communication, reply mail, or compact correspondence. They are larger than #8 5/8 envelopes but smaller than booklet or catalog styles, making them an ideal middle-ground solution for everyday business needs.

There’s a wide variety of #9 envelopes tailored to suit both personal and professional needs.

Popular Types Include:

• Regular #9 Envelopes – Standard mailing envelopes for business letters and inserts.
• Window #9 Envelopes – Designed to display addresses from printed forms, minimizing the need for hand-labeling.
• Double Window #9 Envelopes – Common in financial and billing industries for displaying both sender and recipient info.
• Security Tint Options – Interior patterns add a layer of confidentiality for sensitive content.
• Remittance Styles – Used in donation drives or payment collections with pre-printed information.

#9 envelopes come in paper weights ranging from lightweight 20lb to thicker 32lb options, providing flexibility based on the contents and the durability needed.

Color Choices Include:

• Classic Shades – White, Natural, and Premium White for formal or business communication.
• Pastel Tones – Soft hues like pastel pink, blue, green, and canary yellow for a gentle, approachable presentation.
• Bold Colors – Red, bright blue, or mandarin orange add vibrancy and are perfect for promotional or seasonal mailings.
• Textured Options – Natural linen and grocery bag kraft finishes add tactile sophistication and visual texture.

Whether you're managing day-to-day operations or sending out bulk communications, #9 envelopes serve a variety of purposes.

Common Uses:

• Business Correspondence – Invoices, forms, contracts, and customer communications.
• Reply Envelopes – Included inside larger mailings like marketing kits or billing letters.
• Payment Collection – Donation envelopes and remittance forms for non-profits or billing departments.
• Professional Marketing – Branded envelopes for special promotions or seasonal mailings.

Because of their size and available features, #9 envelopes are widely used for mailing invoices, tax documents, and payment slips. Window and security-tint styles help streamline mailing processes while keeping information private.

Choose #9 envelopes when:

• You need return envelopes to accompany outgoing mailers.
• Mailing compact forms that require a smaller, clean look.
• Sending invoices, payment instructions, or tax documents.
• Creating business reply mail (BRM) for customer feedback or donation replies.
• Coordinating a cohesive professional look with custom-printed logos or designs.

When selecting #9 envelopes, consider these key factors:

• Window vs. Regular – Determine if your printed forms align with standard window positioning.
• Security Tint – Necessary for documents with sensitive information.
• Paper Weight – Lighter options for mass mailing; heavier for a premium feel.
• Closure Type – Choose between traditional gummed or peel & seal for convenience.
• Color and Finish – Match the tone of your mailing, whether formal, creative, or festive.

Example: Business Invoice Mailings

A law office may use white 24lb #9 window envelopes with security tint for mailing invoices and legal correspondence, ensuring the address aligns perfectly with internal forms and remains confidential.

Example: Non-Profit Donation Drives

An organization might include pastel green #9 remittance envelopes inside fundraising letters, encouraging recipients to return donations in branded, user-friendly formats.

Example: Marketing Campaigns

A company launching a seasonal promotion might use bright blue or red #9 envelopes with custom logos and a peel & seal closure to enhance open rates and brand recall.

Our #9 envelopes are crafted with attention to detail and a focus on functionality. From high-contrast tints to high-quality stocks, they’re made to withstand everyday handling while maintaining a crisp, professional look. Available in bulk quantities with competitive pricing, they’re ideal for businesses large and small.

Boost your branding by adding custom elements like logos, return addresses, or messaging. Many of our #9 envelope styles are available with printing services to help reinforce your brand identity and increase engagement.

Our envelopes are used across industries: healthcare, legal, finance, education, non-profits, and more. Their adaptability makes them ideal for everything from mail merges and billing systems to event RSVPs and internal memos.

While primarily used in professional settings, #9 envelopes also serve personal needs like event RSVPs, small invitations, or personal correspondence. Their clean format and wide variety of finishes make them a versatile choice for anyone.

To get the most from your #9 envelopes:

• Match them with #10 outer envelopes for seamless mailings.
• Use security tint for confidential or sensitive materials.
• Take advantage of custom printing for brand consistency.
• Keep a variety of colors and closures on hand for different projects.
• Choose peel & seal options to speed up large mailing tasks.

Compact, functional, and professional, #9 envelopes are a cornerstone of business communication. Whether you need secure invoice mailings, polished marketing materials, or return envelopes that align perfectly with your brand, our range of styles, colors, and features ensures there’s a perfect fit. Add #9 envelopes to your office or personal stationery collection and experience the ease of elevated communication.